Abstract: A laser device (1) includes: a branch waveguide (23) configured to split light propagating from an optical amplifier (10) into a plurality of light beams and output the plurality of light beams; a multi-core waveguide (27) including a plurality of waveguide cores (24 to 26) configured to carry the plurality of light beams input from the branch waveguide (23); and a light reflector (31) optically coupled to a light input/output end of the multi-core waveguide (27). The waveguide cores (24 to 26) are configured to extend along the same direction, and placed in proximity to one another to enable optical coupling between adjacent waveguide cores of the waveguide cores (24 to 26).

Abstract: There are provided: a plurality of optical elements for handling light having different wavelengths; a plurality of collimating lenses individually provided in the optical elements, each of the collimating lenses having a first end facing a main surface of one of the optical elements; an optical multi-demultiplexer using reflection of light caused by a spatial optical system, the optical multi-demultiplexer having a first end facing a second end of each of the collimating lenses; a coupling lens having a first end facing a second end of the optical multi-demultiplexer; an SMF having one end facing a second end of the coupling lens; and an optical block, which is transparent, provided on an optical path between each of the collimating lenses and the optical multi-demultiplexer, the optical path having a small number of reflections in the optical multi-demultiplexer.

Abstract: There are provided: a plurality of optical elements for handling light having different wavelengths; a plurality of collimating lenses individually provided in the optical elements, each of the collimating lenses having a first end facing a main surface of one of the optical elements; an optical multi-demultiplexer using reflection of light caused by a spatial optical system, the optical multi-demultiplexer having a first end facing a second end of each of the collimating lenses; a coupling lens having a first end facing a second end of the optical multi-demultiplexer; an SMF having one end facing a second end of the coupling lens; and an optical block, which is transparent, provided on an optical path between each of the collimating lenses and the optical multi-demultiplexer, the optical path having a small number of reflections in the optical multi-demultiplexer.

Abstract: An optical multiplexer includes a polarizer, a receptacle, a rotator disposed between the polarizer and the receptacle to rotate polarization planes of a pair of linearly polarized light beams in a forward direction and a polarization plane of a light beam in an opposite direction by 45 degrees, the forward direction being from the polarizer toward the receptacle, the opposite direction being from the receptacle to the polarizer, and a birefringent prism disposed between the rotator and the receptacle to multiplex the pair of linearly polarized light beams in the forward direction and to split the light beam in the opposite direction into an ordinary ray and an extraordinary ray. The rotator and the birefringent prism are fixed to the receptacle.

Abstract: A laser device (1) includes: a branch waveguide (23) configured to split light propagating from an optical amplifier (10) into a plurality of light beams and output the plurality of light beams; a multi-core waveguide (27) including a plurality of waveguide cores (24 to 26) configured to carry the plurality of light beams input from the branch waveguide (23); and a light reflector (31) optically coupled to a light input/output end of the multi-core waveguide (27). The waveguide cores (24 to 26) are configured to extend along the same direction, and placed in proximity to one another to enable optical coupling between adjacent waveguide cores of the waveguide cores (24 to 26).

Abstract: An optical multiplexer includes a polarizer, a receptacle, a rotator disposed between the polarizer and the receptacle to rotate polarization planes of a pair of linearly polarized light beams in a forward direction and a polarization plane of a light beam in an opposite direction by 45 degrees, the forward direction being from the polarizer toward the receptacle, the opposite direction being from the receptacle to the polarizer, and a birefringent prism disposed between the rotator and the receptacle to multiplex the pair of linearly polarized light beams in the forward direction and to split the light beam in the opposite direction into an ordinary ray and an extraordinary ray. The rotator and the birefringent prism are fixed to the receptacle.

Abstract: An optical multiplexing/demultiplexing device comprise a plurality of propagation waveguides comprising an input waveguide capable of receiving input light and an output waveguide outputting light of a given wavelength among the wavelengths included in the input light and resonance waveguide that is an optical waveguide provided between adjoining waveguides and extends in a longitudinal direction in which both the adjoining waveguides extend, wherein the adjoining waveguides are an adjoining pair among the propagation waveguides. The distance between the resonance waveguide and each of the adjoining waveguides of the resonance waveguide and a length in the longitudinal direction of the resonance waveguide are set so as to form a transition part, wherein when a light comprising a transition wavelength set to the transition part passes through the transition part of one of the adjoining waveguides, the light of the transition wavelength component shifts to the other adjoining propagation waveguide.

Abstract: A method of manufacturing an optical apparatus having an optical element, a holding member, and a base member includes preparing the holding member and fixing the optical element to the first member. The method further includes fixing a second member of the holding member to the base member and plastically deforming a first member of the holding member and the second member to adjust the position of the optical element.